|
Boro Room -- For Boro-related tips, techniques, and questions. |
2012-01-02, 5:16pm
|
|
Junior Member
|
|
Join Date: Nov 09, 2011
Location: Barrington
Posts: 12
|
|
Boro Question Marbles
Hello all im new to lampworking and boro Ive made a couple of items and i prob know the answer to this but i had different expertations of boro.
Ive made 2 items with boro and cooled them with vermulicite so i could batch anneal them. I made a implosion pendant and a marble. Both items when lifted from the verm. had cracks in them. Now im not sure if i can fix them the pendant exploded when i tried to very slowly reheat it. The marble i havent tried yet.
Here is a picture of the marble.
http://www.lampworketc.com/forums/al...pictureid=5013
[url]http://www.lampworketc.com/forums/album.php?albumid=575&pictureid=5012[/url
I am unsure why these are cracking. If you have any ideas please help. I do know that the pieces should be annealed right away but i do fusing projects also and sometimes my kiln is in use. and while im waiting for the kiln my pieces crack.
J
__________________
I am a stained glass and fusing and soon to be lampworking artist. YAY!!!!!!! To view links or images in signatures your post count must be 5 or greater. You currently have 0 posts.
Im a Veterinary Technician full time at an Emeregency Veterinary Hospital To view links or images in signatures your post count must be 5 or greater. You currently have 0 posts.
|
2012-01-02, 5:21pm
|
|
Borovangelist
|
|
Join Date: Jan 26, 2007
Location: Auburn, MA
Posts: 3,002
|
|
what glass did you use inside for your implosion?
__________________
-Tom
To view links or images in signatures your post count must be 5 or greater. You currently have 0 posts. | To view links or images in signatures your post count must be 5 or greater. You currently have 0 posts. | To view links or images in signatures your post count must be 5 or greater. You currently have 0 posts.
|
2012-01-02, 5:24pm
|
|
Junior Member
|
|
Join Date: Nov 09, 2011
Location: Barrington
Posts: 12
|
|
I used some cinnabar redish and a boro yellow still new so i was playing with a couple of scraps
__________________
I am a stained glass and fusing and soon to be lampworking artist. YAY!!!!!!! To view links or images in signatures your post count must be 5 or greater. You currently have 0 posts.
Im a Veterinary Technician full time at an Emeregency Veterinary Hospital To view links or images in signatures your post count must be 5 or greater. You currently have 0 posts.
|
2012-01-02, 5:28pm
|
|
Borovangelist
|
|
Join Date: Jan 26, 2007
Location: Auburn, MA
Posts: 3,002
|
|
The giant crack looks like thermal stress, vermiculite isn't really good for solid pieces. If you really need to use it, consider taking a little extra time to make sure the temperature's extraordinarily well equalized by slowly making your way out of the flame, but even then you might run into problems.
__________________
-Tom
To view links or images in signatures your post count must be 5 or greater. You currently have 0 posts. | To view links or images in signatures your post count must be 5 or greater. You currently have 0 posts. | To view links or images in signatures your post count must be 5 or greater. You currently have 0 posts.
|
2012-01-02, 5:34pm
|
|
Junior Member
|
|
Join Date: Nov 09, 2011
Location: Barrington
Posts: 12
|
|
It just drives me nuts because I've made plenty of 104 pendants and even a marble and they didn't crack befor I got them in the kiln. I thought boro was supposed to resist cracking and allow you more time to work items sorry still a newbie with all this lol
__________________
I am a stained glass and fusing and soon to be lampworking artist. YAY!!!!!!! To view links or images in signatures your post count must be 5 or greater. You currently have 0 posts.
Im a Veterinary Technician full time at an Emeregency Veterinary Hospital To view links or images in signatures your post count must be 5 or greater. You currently have 0 posts.
|
2012-01-02, 5:54pm
|
|
Pyromaniac
|
|
Join Date: Jun 27, 2006
Location: Out there on the interwebs
Posts: 1,784
|
|
Based on your picture, boro shouldn't be cracking like that. I routinely make pieces larger than that and cool them by setting them down ON TOP of a fiber blanket prior to kiln reheating for additional work or annealing.
What your marble looks like to me is what happens when I forget to keep a larger marble warm while working on the backing pattern, and then I blast it with full heat to melt everything in. I get planar cracks at the lens, as the backing has been kept much warmer than the front. Perhaps you're experiencing a similar problem when removing your punties and flame polishing the scar, only you're not adding enough stress to kill it immediately? Make sure you're not a) using tools which suck heat from the glass where you're holding it (ie: cold metal tools, or using a marble mold to hold the completed piece), and b) that you even out the heat in your pieces prior to removing punties, and again after cleaning up punty mark (and in between if it takes you more than 30 seconds or so to do that).
Another possibility is incompatibility in the glass, either due to mixing up rods or COE shift due to overwork (primarily a concern with greens although reducing can cause issues too).
One more thing that someone very wise in the force once told me is that boro likes to be either very hot, or room temperature (cold)....the in-between states are where problems happen.
__________________
Chris Scala
Fortune Cookie say, "When things go wrong, don't go with them!"
Current Glass-Melting Apparatus:
GTT Lynx powered by 2 5 LPM Oxycons and
a sexy Barracuda running pure tanked Oxy
|
2012-01-02, 6:24pm
|
|
Borovangelist
|
|
Join Date: Jan 26, 2007
Location: Auburn, MA
Posts: 3,002
|
|
I was a little confused too, because I know I've used fiber for some smaller stuff too. Usually, when I see a crack like that it's because I've encased something that doesn't like to be encased, but it doesn't always go all the way through the marble like this did, often it won't even make it to the surface.
__________________
-Tom
To view links or images in signatures your post count must be 5 or greater. You currently have 0 posts. | To view links or images in signatures your post count must be 5 or greater. You currently have 0 posts. | To view links or images in signatures your post count must be 5 or greater. You currently have 0 posts.
|
2012-01-02, 6:54pm
|
Senior Member
|
|
Join Date: Jun 04, 2011
Location: Fredericksburg, VA
Posts: 210
|
|
I get the same thing using annealing beads (which are way better then vermiculite). Cracks all the way through on boro unless very small.
|
2012-01-02, 10:46pm
|
Member
|
|
Join Date: Oct 19, 2011
Posts: 53
|
|
Some collors are worse than others. I have a purple I will not even try to use in a situation like that knowing it will probably crack, and another purple that gives me no issues at all.
|
2012-01-03, 9:28am
|
Senior Member
|
|
Join Date: Jan 29, 2009
Posts: 1,958
|
|
When most people switch from soft glass to boro they don't realize the extra heat that is required to sink into the piece. When working with soft glass you twirl it in the flame for 10 seconds or so and you know the piece is hot all the way through with boro its longer. The heat can sit on the surface but unless you keep it in the flame and let the heat get deeper the centre will not get it. You might be able to see this by taking a bit of black and putting it in the centre of a clear gather (marble) and as you are shaping keep an eye on the black in the middle if it doesn't turn its red glow the heat is not getting in deep. Doing this exercise will give you a sense of timing in how much time in the flame the piece needs for the heat to "get in there".
As far as reheating a piece in the flame for repair its pretty hard to do that without preheating the piece in the kiln. The kiln can bring the piece up to temperature slow enough that it won't shatter along the fractures that are in the glass. If you can see one crack there is probably more that you can't see and the sudden change in temp from the torch will make it shatter.
I know running a kiln cost a few dollars a day but I advise everyone to have it running and start putting your pieces into it from the torch. Get rid of the fiber blanket. I just hate working on a piece just to have it crack in the blanket cause it cooled down to fast or didn't get the proper heat. I know lots of people that "bench cool" pieces but as stated above its tricky.
Hope this helps and ask more questions if any of the points aren't clear.
__________________
To view links or images in signatures your post count must be 5 or greater. You currently have 0 posts.
To view links or images in signatures your post count must be 5 or greater. You currently have 0 posts.
To view links or images in signatures your post count must be 5 or greater. You currently have 0 posts.
|
2012-01-03, 9:53am
|
|
Senior Member
|
|
Join Date: Mar 06, 2011
Location: SF bay area
Posts: 1,470
|
|
I also find that if you are working in your garage during winter, Boro will shock crack much easier because of the cold air. Pieces that I can bench cool on a fiber blanket the rest of the year crack in the winter, so I find that everything must go directly to the kiln.
__________________
Morgan
Bethlehem Champion To view links or images in signatures your post count must be 5 or greater. You currently have 0 posts. To view links or images in signatures your post count must be 5 or greater. You currently have 0 posts.
To view links or images in signatures your post count must be 5 or greater. You currently have 0 posts. To view links or images in signatures your post count must be 5 or greater. You currently have 0 posts. #C-151
|
2012-01-03, 9:57am
|
|
Pyromaniac
|
|
Join Date: Jun 27, 2006
Location: Out there on the interwebs
Posts: 1,784
|
|
I occasionally bench cool smaller pieces/elements, whether due to absent mindedness or whatever but it's important to kiln soak prior to re-heating unless you like cracks.... It's usually a matter of convenience (or distraction), which (usually) doesn't bite me on the ass - but I certainly don't advise it for someone who isn't sure about the parameters.
My biggest killer is when I spend too much time decorating a larger piece and I forget to keep a good base heat on it - and then I forget to garage it so the heat can even out...then POW. Damn it. I'm learning
__________________
Chris Scala
Fortune Cookie say, "When things go wrong, don't go with them!"
Current Glass-Melting Apparatus:
GTT Lynx powered by 2 5 LPM Oxycons and
a sexy Barracuda running pure tanked Oxy
|
2012-01-03, 9:59am
|
|
Senior Member
|
|
Join Date: Mar 06, 2011
Location: SF bay area
Posts: 1,470
|
|
Quote:
Originally Posted by Bunyip
.
My biggest killer is when I spend too much time decorating a larger piece and I forget to keep a good base heat on it - and then I forget to garage it so the heat can even out...then POW. Damn it. I'm learning
|
Been there myself lol
__________________
Morgan
Bethlehem Champion To view links or images in signatures your post count must be 5 or greater. You currently have 0 posts. To view links or images in signatures your post count must be 5 or greater. You currently have 0 posts.
To view links or images in signatures your post count must be 5 or greater. You currently have 0 posts. To view links or images in signatures your post count must be 5 or greater. You currently have 0 posts. #C-151
|
2012-01-03, 12:33pm
|
|
Hobby Junkie
|
|
Join Date: Dec 08, 2009
Location: Perkasie, PA
Posts: 1,967
|
|
I've had a few crack like that when I was doing detailed implosions and somehow got an oblong air bubble trapped near an edge.
__________________
Cori C-R
PS - This is what part of the alphabet would look like if Q and R were eliminated.
To view links or images in signatures your post count must be 5 or greater. You currently have 0 posts.
To view links or images in signatures your post count must be 5 or greater. You currently have 0 posts.
|
2012-01-04, 12:26am
|
|
Junior Member
|
|
Join Date: Nov 09, 2011
Location: Barrington
Posts: 12
|
|
thanks all for all the information. I guess im just gonna have to leave the boro alone till i know my kiln is available. I am in a shed so the temp with heater is around 70. I may have not heated through. Not sure lol only been lamping for 40 days or so.... lol
One last question. Can Boro be annealed with soft glass??
Thank you J
__________________
I am a stained glass and fusing and soon to be lampworking artist. YAY!!!!!!! To view links or images in signatures your post count must be 5 or greater. You currently have 0 posts.
Im a Veterinary Technician full time at an Emeregency Veterinary Hospital To view links or images in signatures your post count must be 5 or greater. You currently have 0 posts.
|
2012-01-04, 12:36am
|
Senior Member
|
|
Join Date: Nov 23, 2007
Location: Portland OR
Posts: 1,332
|
|
short answer is no...
__________________
~Jenny
To view links or images in signatures your post count must be 5 or greater. You currently have 0 posts.
To view links or images in signatures your post count must be 5 or greater. You currently have 0 posts.
To view links or images in signatures your post count must be 5 or greater. You currently have 0 posts.
"In theory, there is no difference between theory and practice; in practice there is." ~ Chuck Reid
|
2012-01-04, 2:10am
|
Alaska Boro
|
|
Join Date: Dec 10, 2009
Location: Anchorage, Alaska
Posts: 1,065
|
|
Quote:
Originally Posted by love2shoot
One last question. Can Boro be annealed with soft glass??
|
See for more discussion....
http://www.lampworketc.com/forums/sh...d.php?t=213941
|
2012-01-04, 5:49am
|
|
Pyromaniac
|
|
Join Date: Jun 27, 2006
Location: Out there on the interwebs
Posts: 1,784
|
|
In our home studio, Kara works only soft glass, and I'm pretty much boro only. When we work together, we set the kiln for soft glass and we both share the kiln. Once the cycle is complete, I just leave the boro in the kiln until my next solo session, or run a batch anneal program when it's convenient. As we anneal our soft glass at 970 (your kiln may vary!), and boro's strain point is around 950, at least SOME strain relief happens in the boro.
So I would say you can do it...kinda, but run a boro cycle afterward just in case. I guess that's why the short answer is "no" (LOL!)
__________________
Chris Scala
Fortune Cookie say, "When things go wrong, don't go with them!"
Current Glass-Melting Apparatus:
GTT Lynx powered by 2 5 LPM Oxycons and
a sexy Barracuda running pure tanked Oxy
|
2012-01-04, 12:37pm
|
|
Save the Numbats
|
|
Join Date: Jul 23, 2005
Location: The Arctic
Posts: 577
|
|
Certain kilns aren't planned the best and have heat gradients which can make it work. For instance, in my AIM 99 the front 4 inches are about 950 when the kiln is set to 1050. That's not the most ideal set up but it can work to anneal soft glass and boro in the same kiln.
|
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
|
|
Posting Rules
|
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
HTML code is Off
|
|
|
All times are GMT -7. The time now is 6:14am.
|